start behind the unicycle by stepping on to the pedal with your leading foot (the one you would start climbing the stairs with) then put your bum on the seat and step over it so you end up with the other foot on the floor in front and dont forget to catch the unicycle with a hand behind you. This teaches you to fall off without falling or dropping the unicycle.
next you want to practice down a hallway or corridor where you can touch both walls, the just one wall.
then its sit on it with your back next to a wall and go for it in the open.
This is how i learnt and if you do it little and often it works.